scholarly journals Statistical Analysis and Stochastic Modelling of Hydrological Extremes

Water ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1861 ◽  
Author(s):  
Hossein Tabari

Analysis of hydrological extremes is challenging due to their rarity and small sample size and the interconnections between different types of extremes and gets further complicated by an untrustworthy representation of meso-scale processes involved in extreme events by coarse spatial and temporal scale models as well as biased or missing observations due to technical difficulties during extreme conditions. The special issue “Statistical Analysis and Stochastic Modelling of Hydrological Extremes”—motivated by the need to apply and develop innovative stochastic and statistical approaches to analyze hydrological extremes under current and future climate conditions —encompass 13 research papers. Case studies presented in the papers exploit a wide range of innovative techniques for hydrological extremes analyses. The papers focus on six topics: Historical changes in hydrological extremes, projected changes in hydrological extremes, downscaling of hydrological extremes, early warning and forecasting systems for drought and flood, interconnections of hydrological extremes and applicability of satellite data for hydrological studies. This Editorial provides an overview of the covered topics and reviews the case studies relevant for each topic.

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Huifeng Bai ◽  
Julie McColl ◽  
Christopher Moore

PurposeFrom an international retailing perspective, this empirical study aims to examine luxury fashion retailers' changing marketing strategies in China.Design/methodology/approachUsing case studies of 14 luxury fashion retailers, qualitative data were collected via 31 semi-structured executive interviews.FindingsBoth standardised global and localised multinational marketing strategies were found to have initially been employed by luxury fashion retailers entering into China. Subsequently, localised multinational strategies became increasingly important for their post-entry operations and business development, particularly in terms of their product strategies. More specifically, as well as the introduction of Chinese brand names, product design has been adapted according to Chinese market conditions, and product portfolios have been adapted to satisfy regional differences. However, localised product sourcing in China is far less common.Research limitations/implicationsAs the findings are generated from China, they may not explain luxury fashion retailers' marketing strategies in other markets. Despite the relatively small sample size, the 14 luxury fashion retailer case studies originate from across a wide range of countries, retail formats and ownership structures and are therefore considered to be varied enough to represent the market.Practical implicationsThe study offers practitioners insights into the success that can be generated by the manipulation of marketing strategies, particularly product strategies, within the world's second biggest luxury market.Originality/valueThis paper extends the current international retailing literature by examining and comparing the motives and practices of luxury fashion retailers and the increasing localisation of their marketing strategies in China as they move from initial market entry into their post-entry operations.


2019 ◽  
pp. 40-46 ◽  
Author(s):  
V.V. Savchenko ◽  
A.V. Savchenko

We consider the task of automated quality control of sound recordings containing voice samples of individuals. It is shown that in this task the most acute is the small sample size. In order to overcome this problem, we propose the novel method of acoustic measurements based on relative stability of the pitch frequency within a voice sample of short duration. An example of its practical implementation using aninter-periodic accumulation of a speech signal is considered. An experimental study with specially developed software provides statistical estimates of the effectiveness of the proposed method in noisy environments. It is shown that this method rejects the audio recording as unsuitable for a voice biometric identification with a probability of 0,95 or more for a signal to noise ratio below 15 dB. The obtained results are intended for use in the development of new and modifying existing systems of collecting and automated quality control of biometric personal data. The article is intended for a wide range of specialists in the field of acoustic measurements and digital processing of speech signals, as well as for practitioners who organize the work of authorized organizations in preparing for registration samples of biometric personal data.


2018 ◽  
Vol 22 (1) ◽  
pp. 54-64
Author(s):  
Angela Gazey ◽  
Shannen Vallesi ◽  
Karen Martin ◽  
Craig Cumming ◽  
Lisa Wood

Purpose Co-existing health conditions and frequent hospital usage are pervasive in homeless populations. Without a home to be discharged to, appropriate discharge care and treatment compliance are difficult. The Medical Respite Centre (MRC) model has gained traction in the USA, but other international examples are scant. The purpose of this paper is to address this void, presenting findings from an evaluation of The Cottage, a small short-stay respite facility for people experiencing homelessness attached to an inner-city hospital in Melbourne, Australia. Design/methodology/approach This mixed methods study uses case studies, qualitative interview data and hospital administrative data for clients admitted to The Cottage in 2015. Hospital inpatient admissions and emergency department presentations were compared for the 12-month period pre- and post-The Cottage. Findings Clients had multiple health conditions, often compounded by social isolation and homelessness or precarious housing. Qualitative data and case studies illustrate how The Cottage couples medical care and support in a home-like environment. The average stay was 8.8 days. There was a 7 per cent reduction in the number of unplanned inpatient days in the 12-months post support. Research limitations/implications The paper has some limitations including small sample size, data from one hospital only and lack of information on other services accessed by clients (e.g. housing support) limit attribution of causality. Social implications MRCs provide a safe environment for individuals to recuperate at a much lower cost than inpatient admissions. Originality/value There is limited evidence on the MRC model of care outside of the USA, and the findings demonstrate the benefits of even shorter-term respite post-discharge for people who are homeless.


Author(s):  
Marianna Rita Stancampiano ◽  
Kentaro Suzuki ◽  
Stuart O’Toole ◽  
Gianni Russo ◽  
Gen Yamada ◽  
...  

Abstract In the newborn, penile length is determined by a number of androgen dependent and independent factors. The current literature suggests that there are inter-racial differences in stretched penile length in the newborn and although congenital micropenis should be defined as a stretched penile length of less than 2.5SDS of the mean for the corresponding population and gestation, a pragmatic approach would be to evaluate all boys with a stretched penile length below 2 cm, as congenital micropenis can be a marker for a wide range of endocrine conditions. However, it remains unclear as to whether the state of micropenis, itself, is associated with any long-term consequences. There is a lack of systematic studies comparing the impact of different therapeutic options on long-term outcomes, in terms of genital appearance, quality of life and sexual satisfaction. To date, research has been hampered by a small sample size and inclusion of a wide range of heterogeneous diagnoses; for these reasons, condition specific outcomes have been difficult to compare between studies. Lastly, there is a need for a greater collaborative effort in collecting standardized data so that all real-world or experimental interventions performed at an early age can be studied systematically into adulthood.


2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Randall S. Porter ◽  
Christine M. Hay

Pasteurella is a genus of commensal bacteria of the oral cavity of several domesticated animals and a common cause of cellulitis after animal bites. Pasteurella has also been reported as a rare cause of endocarditis, with only 35 prior cases of definite Pasteurella endocarditis in the literature. Here, we present a case of Pasteurella multocida endocarditis treated successfully with surgery and antibiosis, as well as a review of the literature with statistical analysis of correlations between risk factors and clinical outcomes, as well as between treatment choices and clinical outcomes. Despite the small sample size, our analysis indicates a statistically significant correlation between comorbid liver disease and mortality, as well as a significant negative correlation between surgical treatment and mortality. This analysis implies a need for surgical management of endocarditis due to Pasteurella species and for more aggressive management of Pasteurella endocarditis in the setting of comorbid liver disease.


Author(s):  
Lisa Cipolotti ◽  
Tianbo Xu ◽  
Bronson Harry ◽  
Joe Mole ◽  
Grace Lakey ◽  
...  

Abstract The voluntary generation of non-overlearned responses is usually assessed with phonemic fluency. Like most frontal tasks, it draws upon different complex processes and systems whose precise nature is still incompletely understood. Many claimed aspects regarding the pattern of phonemic fluency performance and its underlying anatomy remain controversial. Major limitations of past investigations include small sample size, scant analysis of phonemic output and methodologically insufficient lesion analyses approaches. We investigated a large number of patients with focal unilateral right or left frontal (n = 110) or posterior (n = 100) or subcortical (n = 65) lesions imaged with magnetic resonance or computed tomography and compared their performance on the number of overall responses, words produced over time, extremely infrequent/unknown words and inappropriate words generated. We also employed, for the first time parcel-based lesion symptom mapping, tract-wise statistical analysis as well as Bayesian multivariate analysis based on meta-analytically defined functional region of interest, including their interactions. We found that left frontal damage was associated with greater impairment than right frontal or posterior damage on overall fluency performance, suggesting that phonemic fluency shows specificity to frontal lesions. We also found that subcorticals, similar to frontals, performed significantly worse than posteriors on overall performance suggesting that subcortical regions are also involved. However, only frontal effects were found for words produced over time, extremely infrequent/unknown and inappropriate words. Parcel-based lesion symptom mapping analysis found that worse fluency performance was associated with damage to the posterior segment of the left frontal middle and superior gyrus, the left dorsal anterior cingulate gyrus and caudate nucleus. Tract-wise statistical analysis revealed that disconnections of left frontal tracts are critical. Bayesian multivariate models of lesions and disconnectome maps implicated left middle and inferior frontal and left dorsomedial frontal regions. Our study suggests that a set of well localised left frontal areas together with subcortical regions and several left frontal tracts are critical for word generation. We speculate that a left lateralized network exists. It involves medial, frontal regions supporting the process of energization, which sustains activation for the duration of the task and middle and inferior frontal regions concerned with selection, required due to the competition produced by associated stored words, respectively. The methodology adopted represents a promising and empirically robust approach in furthering our understanding of the neurocognitive architecture underpinning executive processes.


2020 ◽  
Vol 57 (2) ◽  
pp. 237-251
Author(s):  
Achilleas Anastasiou ◽  
Alex Karagrigoriou ◽  
Anastasios Katsileros

SummaryThe normal distribution is considered to be one of the most important distributions, with numerous applications in various fields, including the field of agricultural sciences. The purpose of this study is to evaluate the most popular normality tests, comparing the performance in terms of the size (type I error) and the power against a large spectrum of distributions with simulations for various sample sizes and significance levels, as well as through empirical data from agricultural experiments. The simulation results show that the power of all normality tests is low for small sample size, but as the sample size increases, the power increases as well. Also, the results show that the Shapiro–Wilk test is powerful over a wide range of alternative distributions and sample sizes and especially in asymmetric distributions. Moreover the D’Agostino–Pearson Omnibus test is powerful for small sample sizes against symmetric alternative distributions, while the same is true for the Kurtosis test for moderate and large sample sizes.


2000 ◽  
Vol 2 (3) ◽  
pp. 29-39 ◽  
Author(s):  
Judy Wollin ◽  
Helen Dale ◽  
Nancy Spenser ◽  
Anne Walsh

Abstract The aim of this retrospective study was to determine from people with multiple sclerosis (MS) and their families what information would assist a person with newly diagnosed MS — in which format, when, and from whom it should be delivered. Thirty-four Queensland, Australia, residents with MS and 18 family members and friends participated in the main study. Participants were self-selected for this purposive, statewide, cross-sectional study. Nine of the respondents answered open-ended questions in addition to the standard questionnaires, and seven respondents gave in-depth interviews. The respondents recommended that people with a recent MS diagnosis and their families be given a wide range of information reflective of their personal needs. The information should be provided in person (in both group and individual sessions). They preferred to receive the information from their physicians and the staff of the Multiple Sclerosis Society. Research aimed at cures and therapies, as well as counseling and support services, should be discussed early in the course of the disease. Because of the small sample size and retrospective design, additional studies with larger populations are suggested to confirm these results and their cross-cultural applicability.


Author(s):  
Elaine Husni ◽  
Madonna Michael

The epidemiological studies of psoriatic arthritis (PsA) is quite challenging as our understanding of the disease is evolving. A wide range of incidence and prevalence is reported among different countries suggesting genetic and environmental factors influencing the epidemiology of PsA. Other contributing factors accounting for the wide range and variation of PsA epidemiology include age and gender variations, ethnicity, lack of precise case definition, and small sample size. A high level of suspicion in patients with pre-existing psoriasis, and collaborative efforts shared between primary care physicians (PCP), dermatologist, and rheumatologist, will enhance early detection and management of PsA, subsequently improving overall patient outcomes, and quality of life.


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